MC1-Conclusion

=Marsh Creek 1 - Conclusion=

Marsh Creek Site 1 is an exaggerated creek gouged open by repeated flooding episodes, situated at an elevation of 1012 ft above sea level, and positioned in a well established residential neighborhood. Site 1 is near the headwater for the Marsh Creek watershed as well as for the Chattahoochee watershed. The health of the continually expanding stream plays an integral part in the health of Sandy Springs' rivers, streams, and ecosystems. This investigation illustrates the need for erosion-control procedures in the Marsh Creek watershed. The recent erosion restoration near the culvert is clearly not sufficient for Marsh Creek and should be extended along the upstream banks on either side. The directly adjacent watershed in this site area is predominantly lawns and gardens. However, the larger perspective of the site shows much infrastructure and commercial development of impervious surfaces, which feed large amounts of swiftly moving, powerful rainwater into Marsh Creek.

The chemical and physical results for Marsh Creek Site 1 reflect the heat and pollution problems and were limited by the ephemeral nature of this stream. The following days brought extremely hot, dry weather, which further impacted data and the ability to collect data. Considering these facts, the pH balance for the two days of collection were 6 and 6, showing a small tendency toward higher acidity levels. The water temperatures were above the healthy range, at 20 degrees Celsius for all four tests. The paved surface runoff and the ambient air temperature influence the water temperature. The Dissolved Oxygen levels measured 5.5 and 5.4 ppm on the first visit and 3 and 3.2 ppm on the second visit. The first Dissolved Oxygen reading results were higher due to the recent rain event. The second site visit reading results were much lower, but were still within the healthy range. Conductivity measures the ability for the water to pass electric current and is defined in microsiemens per centimeters. Healthy levels are between 150 and 500 μS/cm. The readings from Marsh Creek site 1 were 90 and 90 μS/cm at the first site visit and 100 and 100 μS/cm at the second site visit. These readings indicate poor stream water conductivity.

The bacterial results show Coliform counts of 2200 on the first site visit and 9766 on the second site visit. The first site visit took place after a series of storms had passed through the area, and the expectation would be to see higher coliform levels. Yet that was not the case. The stream water had evaporated and drained away, with the remaining water settling into a series of staggered pools. The remaining pooled water was more concentrated, resulting in the elevated coliform levels.

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